Scheimpflug Imaging Criteria for Identifying Eyes at High Risk of Acute Angle Closure

Purpose: to compare anterior segment and ocular biometric parameters in unaffected fellow eyes of patients with a previous attack of acute angle closure (aac), primary angle closure suspect (pacs) eyes, and normal eyes; and to identify eyes at high risk of aac among primary angle closure suspects. methods: in this case-control study, 16 unaffected fellow eyes of patients with a previous attack of aac (group i), 20 pacs eyes (group ii) and 18 normal eyes (group iii) underwent pentaca and a-scan echography.results: mean anterior chamber volume was 72±18, 77±18 and 176±44 ?l in groups i, ii, and iii, respectively (p<0.001). corresponding values for anterior chamber angle in the same order were 24.8±4.6, 22.6±6.3 and 35.8±6.9 degrees (p<0.001), and that for anterior chamber depth measured from the corneal endothelium were 1.80±0.26, 1.93±0.23 and 3.13±0.59 mm, respectively (p<0.001). using receiver operating characteristic (roc) curves, anterior chamber volume ≤100 μl was associated with a high risk of aac with sensitivity of 93.3% and specificity of 100%. corresponding values for anterior chamber depth ≤2.1 mm were 86.7% and 100%, and that for anterior chamber angle ≤26° were 73.3% and 88.2%, respectively. age, sex, central corneal thickness, and lens thickness were comparable among the study groups (all p values >0.05). conclusion: eyes with anterior chamber volume ≤100 μl, depth ≤2.1 mm and angle ≤26° may be considered at high risk for developing aac. these criteria could be helpful for making decisions regarding prophylactic laser peripheral iridotomy